Draft regulator



E. .C. WILEY DRAFT REGULATOR Filed March 25, 1919 WITNESSES ATTO R N EY Patented Jan. 27, 1925.

UNITED STATES EDGAR O. WILEY, OF LYNOHBURG, VIRGINIA. ASSIGNOR TO COMBUSTION REGULATOR CO., INC., OF LYNOHBURG, VIRGINIA, A CORPORATION OF VIRGINIA.

nRAr'r REGULATOR.

Application filed March 25,1919. scrim No. 285,034.

To all whom it may concern:

Be it known that I, EDGAR C. WILEY, a citizen of the United States, residing at Lynchbur in the county of Campbell and State of irginia, have invented'new and useful Draft Re lators, of which the following is a specification.

This invention has reference to draft regulators of the type shown and described in Letters Patent #1,208,432, granted to me on December 12, 1916, and its object is to avoid the effects of the distillation of the volatile gases at a rapid rate by highly incandescent fuel when there is an insuflicient supply of air to complete the combustion of the gases, such conditions sometimes occurring when the automatic damper cuts off the air supply beneath the grates for purposes of checking combustion without at the same time admitting a sufficient supply of air over the fuel bed to complete the combustion ofthe gases. Even though such an objectionable condition lasts but a short time the incompletely burned gases are driven off in large quantities and cause a quick de osition of thick coatingsof soot within the iler flues and on the heat absorbing surfaces.

With the present invention supplementary air'is introduced into the combustion chamher in synchronism with the movement of the main air supply damper cuttin off the supply under the grate, whereby t e gases rcachm the combustion chamber are met by a su cient quantity of air to'aflord perfect combustion and thus avoid depositions of soot. The invention contemplates the provision of a wall having many air passages through it, which for convenience may be termed a perforated wall, whereby to admit a limited quantity of fresh air over the top of the fuel bed to aid in the combustion of gases arisingfrom the fuel bed after the su ply of fresh air underneath the grates has n closed or very nearly closed by the movements of the automatically contro ed damper. 1

With the structure shown and described in the aforesaid Letters Patent, and also 7 with other automatic boiler draft controls, there occurs a time just after the damper admitting air to the ash-pit has closed when the fuel bed or charge is left in a highly incandescent state, thereby distillin vo atile gases at a rapid rate without there ing any supply of air to complete the combustion of the gases. I

The supplementary air supply is so designed as to be insuflicient in itself for checking purposes, this being taken care of by an air check admitting air over the fire bed as in the aforesaid Letters Patent, but the supplementary air is arranged to cause the combustion of gases produced whenthe air draft to the grate has been closed or has very nearly reached the closed position, and while the supplementary air may serve to'some extent for checking purposes, its main purpose is to provide for the interval between the time when the air is cut off from the grate and the time when checking air is admitted to the combustion chamber. 7

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding, however, that the invention is not confined to any strict conformity with the showi of the drawing, but may be changed an modified so long as such changes and modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawing 2- Figure 1 is a central vertical front to rear section of a furnace embodying the invention.

Figure 2 isa similar view showing a somewhat modified form of the invention.

Referring to the drawing, there is shown a portion 0 a furanc-e 1, which may be taken as typical of a heating furnace ada table for use in a vapor heating system, suc for instance, as is customarily em loyed in residences and other buildings, a though the invention may be used wherever regulation of the kind it rovides is desirable. The furnace shown as the usual ash-pit 2, grate 3, combustion chamber 4 and smoke pipe con nection 5, none of which need be described in detail. A

At the rear of the ash pit there is a duct 6 connected to another duct 7 which may be formed in a casting 8 containing still other. v

ducts 9, and 10. These ducts 7, 9 and 10 are arranged at the rear of the furnace and have op n gs or ports 11, 12 and13 0 g a.

the atmosphere, and in the partic ar sho ing of the drawing, these so 'far described, with respect-to the draftopeni or ports are grouped together so as to eclose1y adjacent. This is because the openings or ports may then be controlled by a single convex damper plate '14, the ports 11, 12 and 13 being correspondingly concave in the particular showing of the drawing, the construction being similar to that shown in the aforesaid Letters Patent.

The plate or damper 14 is mounted in supporting arms 15 to turn on an axis corresponding to that of the curvature of the plate 14 and this damper plate is counter-' balanced b a weight 16. The damper is controlled y a link'17 fastened to an arm 17 on the damper plate,and this link is in turn under the control of a lever 18 engaged by a pressure responsive device 19 movable by boiler pressure, or any suitable controlling means adapted to steam or hot water boilers, may be employed.- The parts regulator, may be such as are shown and de scribed in the aforesaid Letters Patent and may operate in like manner thereto, so that no'extended description of the construction or operation is herein nece$a The ducts 9 and 10 are divi d ed by a wall or plate 20 having numerous ages 21 therethrough which may be, though are no'tnecessarily, in the form of perforations and are made relatively small. The duct 9 communicates with the fire chamber 4, through another duct 22, and in the structure shown in Figure 2 the duct 10 also communicates with the smoke flue 5 by way of a passage 23. Whether in accordance with one or the other of these arrangements, the

duct '10 with its inlet port 13 and the plate :20 with the passages 21 therein form an air inlet for the admission of air to the duct 22 leading to the combustion chamber, which air inlet is supplemental to the duct 9 with its inlet ort 12.,

l-Vith t e device of the invention, when the firebox 4 .is filled with fresh fuel, such fuel heats up rapidly and the steam pressure, or water temperature in a hot water boiler, is brought upv to a point wherevthe automatic damper regulator causes the movement of the damper plate 14 to an extent to practicallyjclose the duct 7. and then the duct 10 will be 'n to open to the atmosphere therehy admitting air to the duct 10. Such air is drawn through the holes in the perforated plate 20 into the duct 9 and from thence through the duct 22 into the fire chamber and over the bed of fire where such supplementary air will unite with the gases arising from the fuel bed. As the damper advances so as to entirely close" the duct 7 and completely shut off the air underneath the grate 3, such'secondary or supplementary air is sufficient to complete the combustion of gases being'distilled from the fuel bed purel because of the intense heat of such fuel If the boiler pressure,or water temperature, continues to increase there 0ccuis a further movement of the damper plate 11 which, after an interval of time begins to and may ultimately fully open the 12, thus admitting fresh air in chec quantities in the device shown in the aforesaid Letteis Patent, and this checking functionmay be augmented by air entering through the port 13 and finding its way through the passages 21 into the flue 9.

In the structure shown in Figure 2, the opening of the ort 13 admits air to the smoke inlet or ue and supplementary air through the passages 21 to the space in the fire chamber above the bed of coal. So for as the perforated wall 20 is concerned its function is similar in the structures shown in both Figures 1 and 2. Aside from this the structum of Figures 1 and 2 are similar to the structures set forth in the afomaid Letters Patent, that is, in Figure 1' there is shown a two-phase construction admitting air to the ash-pit and then to the fire chamber as the ash-pit air is cut off, for and checking purposes, and in Figure there is shown a three-phase construction, in which air is admitted to the ash-pit, then to the smoke fiue and then to the file chamber, the admi sion of air to the smoke flue and fire chamber being for checking purposes and occurring in the order named.

The air reaching the fire chamber by way of the perforations 21 first serves for combustion purposes with respect to the gnaw evolved from the fuel after the main supply of air is nearly or fully cut off, and then as the checking air is admitted through the port 12 the supplementa air admitted through the perforations 21 as the effectof increasing the checking air at the beginning of the checking operation with respect to the fire chamber. However, the rime purpose of the erforated wall 20, w ch wall may be repliiced by any means answering the same purpose, is to automatically supply sup lementary air to cause the comp ete com ustion of gases distilled from the fuel and inthe unburned state reaching the heat absorbing surfaces because of the lack of air su ply through the grate due to-the closthe ash-pit of the furnace, another duct leading to the combustion chamber of the furnace, and a third duct communicating with the secondnamed duct through a plurality of relatively small openings, and a damper common to the ducts and movable with relation thereto in a direction to close the duct to the ash-pit, open one of the other ducts to cause air to flow through the relatively small openings into the second-named duct and through the latter to the fire chamher and finally open the third duct to the fire chamber to supply air thereto in checking quantities.

3. A draft regulator for furnaces provided with draft and other air ducts all communicating with the atmosphere at one end and there provided with ports in close relation, two adjacent ducts having a perforated wall between them whereby air ma reach one of the ducts through either or both of their ports, and a damper movable across the ports in succession.

4. A draft regulator for furnaces provided with draft and other air ducts all communieating with the atmosphere at one end and there provided with ports in close relation, those ducts other than the draft duct communicating through a perforated wall with one of the ducts in turn communicating with the fire chamber of the furnace and the other duct with the smoke flue of the furnace, and a damper movable across the .orts in succession, whereby air may be a mitted to the ashit for combustion urposes, air may be admitted to the smoke ue and fire chamber for checking purposes, and supplementary air may be admitted to the fire chamber for combustion purposes.

5. A draft regulator for furnaces comprising an air duct leadin to the ash-pit of the furnace and at the en remote from the ashpit having a port communicating with the atmosphere, another duct adjacent to the first-named duct and leading directly into the fire chamber of the furnace and at the end remote from the fire chamber provided with a port leading to the atmosphere and closely adjacent to the first-named port, and a third duct on the side of the second duct remote from the first-named duct and divided from the second duct by a perforated wall, said 7 6. A draft regulator for furnaces comprisr ing an air duct leadin to the ash-pit of the furnace and at the en remote from the ashpit having a port communicating with the atmosphere, another duct adjacent to the first-named duct and leading directly into the fire chamber of the furnace and at the end remote from the fire chamber provided with a port leadin to the atmosphere and closely adjacent to t e first-named port, and a third duct on the side of the second duct remote from the first-named duct and divided from the second duct by a perforated wall, said third duct having a port adjacent to the second-named port and-leading to the atmosphere, and a damper movable in order over the ports, said damper being of a size and having a range of travel to wholly cover the second-named port and simultaneously cover the major portion of both the other ports.

' 7. A draft regulator for furnaces having ducts with adjacent ports leading to the atmosphere, two of the ducts having a division wall between them provided with numerous relatively small perforations, and a damper movable across the ports to open or close them in order, one of the ducts leading to the ash-pit of the furnace and the other ducts communicating with the fire chamber of the furnace, one directly and the other through the perforated wall.

8. A draft regulator for furnaces having a duct leading to the ash-nit of the furnace and at the end remote therefrom having a port leading to the atmosphere, another duct leading to the fire chamberof the furnace and at the end remote from said fire chamber provided with a port leading to the atmosphere and closely adjacent to the first-named port, and a third duct separated from the second-named duct by a wall provided with numerous relatively small perforations, through which the third duct communcates with the second duct and by the latter to the fire chamber of the furnace, said third duct leading into the smoke flue of the furnace and having a rt opening to the atmosphere adjacent to t e second-named port, and a damper movable into controlling relation to the ports and of a size and extent of travel to open or close the ports successively with one or more of the ports always in communication with the atmosphere.

In testimony, that I claim the foregoing as my own, I have hereto affixed my signature.

E. J. F. WILSON, F. B. STANLEY. 

